Overzealous filtering a sign of things to come?

Published26th, May 2017

Today has seen a very interesting development over at ISPreview.co.uk. They reported this morning1 that anyone who uses Sky Broadband was unable to access their site if they had their ‘Shield’ (Parental Control) service activated. It later transpired that Vodafone Home Broadband customers had a similar problem. Investigations showed that the site was being blocked because it had been flagged under their ‘phishing and malware category. Concerned that their site had been hacked or someone had managed to slip a nasty virus onto the site somehow, they carried out various scans and security checks, but all came back clean.

They then turned to the Quttera’s2 scanner and it is there that the story takes an interesting, and amusing turn.

Conservative Manifesto blocked

Quttera reported that two articles on ISPreview.co.uk contained links to external sites which had, themselves been blacklisted for malware reasons. And as it turned out, the problem was with the Amazon’s Cloud server, and specifically the one which was hosting the PDF version of the Conservative Party’s 2017 Manifesto (s3.eu-west-*.amazonaws.com). This raises a number of interesting points. Firstly, Sky Broadband appears to have blocked an entire site, which has several hundred thousand pages, as a result of a problem on an external link, which is linked to on just one page. In their article detailing the saga, ISPreview.co.uk describe this as “overzealous filtering at its worst”, which is something I am inclined to agree with.

They also suggested that the nature of the content in question could lead to some claiming a political conspiracy, but I am not so sure I agree with that.

Sky Broadband’s wrongful blocking habit

This is not the first time that Sky Broadband has been guilty of blocking websites without any real reason. As ISPreview.co.uk themselves reported, in 2015 an effort by Sky Broadband to block a proxy site for the Pirates Bay3 ended up with CloudFlare’s CDN being blocked as well. A similar effort to block EZTV4 saw them accidentally block hundreds of popular websites, including Crystal Palace FC official site, the Radio Times website, and an official Taylor Swift site., whilst another attempt to block the same site5 saw Imgur.com being blocked as well as sites like Facebook and TorrentFreak having restricted access. The block on ISPreview.co.uk was lifted within a few hours with a spokesperson for Sky Broadband saying “Our Broadband team were advised that the ISPreview.co.uk website contained a threat of Malware of Phishing and for this reason, it was automatically blocked. After manually investigating, we identified that there was no risk from the site itself and removed the block.”

The broader issue

It is easy to look at this issue and think of it as a small problem which was resolved in a few hours.

But it actually illustrates a real problem with the increased use of automatic and forced filters. Whilst it is obviously important to restrict access to dodgy sites which are spreading malware and other viruses, overzealous filtering can lead to sites being wrongly blocked quite easily. While ISPreview.co.uk managed to get the block lifted, other sites might not be so lucky. The link to a political document, especially one which is proposing worrying new clampdowns6 on online freedom is more ironic that evidence of a conspiracy. As sites are required to block access to more and more content at the behest of the government, getting incorrectly applied blocks removed is likely to get harder.

The road also has a worrying habit of leading towards censorship for reasons other than sites posing a risk to visitors. Political and moral censorship is just a stone’s throw away once ISP filtering becomes as sensitive as this. All which is yet more evidence of why a VPN is such a vital tool for internet users.

A VPN allows users to bypass censorship, whether it is being applied by an authoritarian government, as is the case in countries such as China, Russia, and Iran, or an overzealous ISP. A VPN is an affordable, easy-to-use tool which is already seeing a spike in users who are drawn to their online security and privacy benefits. But they are also the perfect solution to online censorship too.

And whilst everyone in the UK should now be able to see ISPreview.co.uk, regardless of which ISP they are using, there are many more legitimate sites which are blocked here and policy proposals suggest the situation is likely to get a whole lot worse.